趙惠文王六年(nian)(前(qian)293年(nian)),封公(gong)子(zi)趙勝為(wei)平(ping)原君(jun)(jun)。平(ping)原君(jun)(jun)喜好名(ming)家論(lun)辨之言,公(gong)孫龍(long)遂為(wei)平(ping)原君(jun)(jun)的門(men)客。
趙(zhao)惠(hui)文王(wang)(wang)十五年(前(qian)284年),燕(yan)昭王(wang)(wang)欲攻齊國(guo),公(gong)孫(sun)龍帶領弟子,從(cong)趙(zhao)國(guo)趕到(dao)燕(yan)國(guo),力圖(tu)勸其“偃兵(bing)”。燕(yan)王(wang)(wang)滿口答應,公(gong)孫(sun)龍卻表示不可相信,說道:當初大(da)王(wang)(wang)招納欲破齊、能破齊的(de)“天下之(zhi)士”到(dao)燕(yan)國(guo)來(lai),后來(lai)終于破齊。而今(jin)“諸侯之(zhi)士在大(da)王(wang)(wang)之(zhi)本朝者,盡善用(yong)兵(bing)者”,所(suo)以我(wo)認(ren)為(wei)大(da)王(wang)(wang)不會偃兵(bing)。他用(yong)這種“循實則名(ming)”的(de)方法猜透了燕(yan)王(wang)(wang)的(de)真實用(yong)心,使燕(yan)王(wang)(wang)無言以對。
十六年(前283年),秦(qin)(qin)(qin)國與趙(zhao)(zhao)(zhao)(zhao)國盟(meng)會締約:“秦(qin)(qin)(qin)之所欲為,趙(zhao)(zhao)(zhao)(zhao)助(zhu)之;趙(zhao)(zhao)(zhao)(zhao)之所欲為,秦(qin)(qin)(qin)助(zhu)之。”答應(ying)相(xiang)互援助(zhu)。不久,秦(qin)(qin)(qin)興兵攻魏(wei),趙(zhao)(zhao)(zhao)(zhao)欲救魏(wei)。秦(qin)(qin)(qin)王(wang)(wang)使(shi)人責(ze)備趙(zhao)(zhao)(zhao)(zhao)惠文王(wang)(wang)不遵守盟(meng)約。趙(zhao)(zhao)(zhao)(zhao)王(wang)(wang)將(jiang)此事告(gao)知平(ping)原君(jun)。公孫龍向(xiang)平(ping)原君(jun)建議說(shuo):趙(zhao)(zhao)(zhao)(zhao)也可以派遣使(shi)者(zhe)去責(ze)備秦(qin)(qin)(qin)王(wang)(wang)說(shuo),趙(zhao)(zhao)(zhao)(zhao)國想(xiang)援救魏(wei)國,秦(qin)(qin)(qin)國卻攻打魏(wei)國,是秦(qin)(qin)(qin)國首先(xian)違背了盟(meng)約。
十(shi)九年(nian)(前280年(nian)),公孫龍又與趙(zhao)惠文(wen)王論偃(yan)兵之(zhi)事(shi)。趙(zhao)王問公孫龍說(shuo):“寡人(ren)事(shi)偃(yan)兵十(shi)余年(nian)矣,而不(bu)成(cheng),兵不(bu)可(ke)偃(yan)乎?”公孫龍回答說(shuo):“偃(yan)兵之(zhi)意(yi),兼(jian)愛(ai)(ai)天下之(zhi)心(xin)也。兼(jian)愛(ai)(ai)天下,不(bu)可(ke)以虛名為也,必有其實(shi)。”并指(zhi)出趙(zhao)惠文(wen)王當秦得地而縞素布總(zong),齊亡地而加膳置酒,并不(bu)真正具有兼(jian)愛(ai)(ai)之(zhi)心(xin),故(gu)不(bu)能行偃(yan)兵之(zhi)實(shi)。
趙(zhao)(zhao)(zhao)孝成王九年(前(qian)257年),秦兵攻趙(zhao)(zhao)(zhao),圍邯鄲。平原(yuan)(yuan)君(jun)使人(ren)(ren)向魏國(guo)求(qiu)救(jiu)。信(xin)陵君(jun)率兵救(jiu)趙(zhao)(zhao)(zhao),邯鄲得以保存。虞卿為(wei)(wei)(wei)平原(yuan)(yuan)君(jun)向趙(zhao)(zhao)(zhao)王請封。公孫龍(long)連(lian)夜(ye)駕車入見平原(yuan)(yuan)君(jun),認為(wei)(wei)(wei)此舉(ju)甚不可(ke)行,指(zhi)出“王舉(ju)君(jun)而(er)(er)(er)相(xiang)趙(zhao)(zhao)(zhao),割(ge)東武城而(er)(er)(er)封君(jun)者”并不是(shi)(shi)因(yin)為(wei)(wei)(wei)平原(yuan)(yuan)君(jun)的才智能力為(wei)(wei)(wei)趙(zhao)(zhao)(zhao)國(guo)所(suo)獨有的,而(er)(er)(er)是(shi)(shi)因(yin)為(wei)(wei)(wei)平原(yuan)(yuan)君(jun)是(shi)(shi)趙(zhao)(zhao)(zhao)王親(qin)戚的緣故。而(er)(er)(er)“一解國(guo)患,欲(yu)求(qiu)益地,是(shi)(shi)親(qin)戚受(shou)封而(er)(er)(er)國(guo)人(ren)(ren)計功也”,即計國(guo)人(ren)(ren)之(zhi)功于親(qin)戚名下。因(yin)此建(jian)議(yi)平原(yuan)(yuan)君(jun)不要受(shou)封,平原(yuan)(yuan)君(jun)聽(ting)從了公孫龍(long)的建(jian)議(yi),并由此對其(qi)益加看重(zhong)。
他可(ke)能較長(chang)時間作(zuo)平(ping)(ping)原(yuan)君(jun)的(de)門客(ke)。《史記·平(ping)(ping)原(yuan)君(jun)虞卿(qing)列傳》說(shuo),“平(ping)(ping)原(yuan)君(jun)厚待(dai)公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)”。約(yue)(yue)于(yu)公(gong)(gong)(gong)(gong)(gong)(gong)(gong)元(yuan)前(qian)279年(nian)(nian)至前(qian)248年(nian)(nian)間,公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)曾從(cong)趙(zhao)(zhao)(zhao)國(guo)(guo)帶領(ling)弟子(zi)(zi)到燕(yan)國(guo)(guo),《呂(lv)氏(shi)春(chun)秋·應言(yan)》載(zai),是(shi)(shi)為(wei)(wei)(wei)了說(shuo)燕(yan)昭(zhao)王(wang)(wang)(wang)以(yi)“偃兵”。燕(yan)王(wang)(wang)(wang)雖然表示同意,公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)卻當面對燕(yan)王(wang)(wang)(wang)說(shuo)。“諸侯之(zhi)(zhi)士(shi)在大王(wang)(wang)(wang)之(zhi)(zhi)本朝者(zhe)(zhe),盡(jin)善(shan)(shan)用兵者(zhe)(zhe)”,所(suo)(suo)以(yi)我認為(wei)(wei)(wei)大王(wang)(wang)(wang)不(bu)會(hui)偃兵,燕(yan)昭(zhao)王(wang)(wang)(wang)無言(yan)應答。公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)又曾游(you)魏,與公(gong)(gong)(gong)(gong)(gong)(gong)(gong)子(zi)(zi)牟論(lun)學。在趙(zhao)(zhao)(zhao)國(guo)(guo),《呂(lv)氏(shi)春(chun)秋·審(shen)應覽》載(zai),公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)曾與趙(zhao)(zhao)(zhao)惠文(wen)王(wang)(wang)(wang)論(lun)偃兵。趙(zhao)(zhao)(zhao)王(wang)(wang)(wang)問公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)說(shuo):“寡人(ren)(ren)事(shi)偃兵十余(yu)年(nian)(nian)矣,而(er)不(bu)成(cheng),兵不(bu)可(ke)偃乎(hu)?”公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)回答說(shuo):“趙(zhao)(zhao)(zhao)國(guo)(guo)的(de)藺、離(li)石兩地被秦(qin)(qin)侵占,王(wang)(wang)(wang)就穿上喪(sang)國(guo)(guo)的(de)服裝(zhuang),縞素布總;東攻齊得(de)城(cheng),而(er)王(wang)(wang)(wang)加膳(shan)置酒(jiu),以(yi)示慶祝。這怎能會(hui)偃兵?”《呂(lv)氏(shi)春(chun)秋·淫辭》說(shuo):秦(qin)(qin)國(guo)(guo)跟趙(zhao)(zhao)(zhao)國(guo)(guo)訂(ding)立盟(meng)約(yue)(yue):“秦(qin)(qin)之(zhi)(zhi)所(suo)(suo)欲(yu)為(wei)(wei)(wei),趙(zhao)(zhao)(zhao)助(zhu)(zhu)之(zhi)(zhi);趙(zhao)(zhao)(zhao)之(zhi)(zhi)所(suo)(suo)欲(yu)為(wei)(wei)(wei),秦(qin)(qin)助(zhu)(zhu)之(zhi)(zhi)。”過(guo)了不(bu)久。秦(qin)(qin)興兵攻魏,趙(zhao)(zhao)(zhao)欲(yu)救魏。秦(qin)(qin)王(wang)(wang)(wang)使(shi)(shi)人(ren)(ren)責(ze)備趙(zhao)(zhao)(zhao)惠文(wen)王(wang)(wang)(wang)不(bu)遵守盟(meng)約(yue)(yue)。趙(zhao)(zhao)(zhao)王(wang)(wang)(wang)將這件事(shi)告訴平(ping)(ping)原(yuan)君(jun)。公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)給(gei)平(ping)(ping)原(yuan)君(jun)出主(zhu)意說(shuo),趙(zhao)(zhao)(zhao)可(ke)以(yi)派遣使(shi)(shi)者(zhe)(zhe)去責(ze)備秦(qin)(qin)王(wang)(wang)(wang)說(shuo),秦(qin)(qin)不(bu)幫助(zhu)(zhu)趙(zhao)(zhao)(zhao)國(guo)(guo)救魏,也(ye)是(shi)(shi)違背(bei)盟(meng)約(yue)(yue)。趙(zhao)(zhao)(zhao)孝成(cheng)王(wang)(wang)(wang)九(jiu)年(nian)(nian)(公(gong)(gong)(gong)(gong)(gong)(gong)(gong)元(yuan)前(qian)257年(nian)(nian)),秦(qin)(qin)兵攻趙(zhao)(zhao)(zhao),平(ping)(ping)原(yuan)君(jun)使(shi)(shi)人(ren)(ren)向魏國(guo)(guo)求救。信陵君(jun)率兵救趙(zhao)(zhao)(zhao),邯(han)鄲得(de)以(yi)保存(cun)(cun)。趙(zhao)(zhao)(zhao)國(guo)(guo)的(de)虞卿(qing)欲(yu)以(yi)信陵君(jun)之(zhi)(zhi)存(cun)(cun)邯(han)鄲為(wei)(wei)(wei)平(ping)(ping)原(yuan)君(jun)請求增加封地。公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)聽說(shuo)這件事(shi),勸(quan)阻平(ping)(ping)原(yuan)君(jun)說(shuo):“君(jun)無覆軍殺將之(zhi)(zhi)功,而(er)封以(yi)東武城(cheng)。趙(zhao)(zhao)(zhao)國(guo)(guo)豪(hao)杰之(zhi)(zhi)士(shi),多在君(jun)之(zhi)(zhi)右,而(er)君(jun)為(wei)(wei)(wei)相(xiang)(xiang)國(guo)(guo)者(zhe)(zhe)以(yi)親(qin)故。夫君(jun)封以(yi)東武城(cheng),不(bu)讓無功,佩趙(zhao)(zhao)(zhao)國(guo)(guo)相(xiang)(xiang)印,不(bu)辭無能,一解國(guo)(guo)患,欲(yu)求益地,是(shi)(shi)親(qin)戚受封,而(er)國(guo)(guo)人(ren)(ren)計(ji)功也(ye)。為(wei)(wei)(wei)君(jun)計(ji)者(zhe)(zhe),不(bu)如勿(wu)受便。”平(ping)(ping)原(yuan)君(jun)接(jie)受了公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)的(de)意見,沒有接(jie)受封地。公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)善(shan)(shan)于(yu)辯(bian)論(lun)。《公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)子(zi)(zi)·跡(ji)府(fu)》說(shuo),公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)與孔(kong)穿在平(ping)(ping)原(yuan)君(jun)家(jia)相(xiang)(xiang)會(hui),談辯(bian)公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)的(de)“白(bai)馬(ma)(ma)非馬(ma)(ma)”。晚年(nian)(nian),齊使(shi)(shi)鄒衍過(guo)趙(zhao)(zhao)(zhao),平(ping)(ping)原(yuan)君(jun)使(shi)(shi)與公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)論(lun)“白(bai)馬(ma)(ma)非馬(ma)(ma)”之(zhi)(zhi)說(shuo)。公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)由是(shi)(shi)遂詘(chu),后不(bu)知所(suo)(suo)終。公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)的(de)主(zhu)要思想,保存(cun)(cun)在《公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)子(zi)(zi)》一書中。《漢書·藝文(wen)志》名(ming)(ming)家(jia)有《公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)子(zi)(zi)》十四篇。今存(cun)(cun)六(liu)篇。《跡(ji)府(fu)》,是(shi)(shi)后人(ren)(ren)匯集公(gong)(gong)(gong)(gong)(gong)(gong)(gong)孫(sun)(sun)(sun)(sun)(sun)龍(long)(long)(long)的(de)生平(ping)(ping)言(yan)行(xing)寫成(cheng)的(de)傳略。其(qi)余(yu)五篇是(shi)(shi):《白(bai)馬(ma)(ma)論(lun)》、《指物(wu)論(lun)》、《通變論(lun)》、《堅白(bai)論(lun)》、《名(ming)(ming)實論(lun)》,其(qi)中以(yi)《白(bai)馬(ma)(ma)論(lun)》最著名(ming)(ming)。
公(gong)孫龍(long)的哲學(xue)思(si)想,《淮南子》說,公(gong)孫龍(long)"別同異,離堅白"。
他與(yu)惠施(shi)的(de)"合同異"說(shuo)正相(xiang)反,完全脫離(li)感性認識,只強調概念的(de)邏輯(ji)分析,具有十分濃厚(hou)的(de)形而上學特色。但在邏輯(ji)學上,他的(de)貢(gong)獻是值得重視的(de)。
公孫(sun)龍(long)的(de)(de)(de)(de)"離(li)(li)(li)(li)堅(jian)(jian)(jian)(jian)(jian)(jian)白(bai)(bai)"學(xue)說(shuo)是(shi)(shi)(shi)(shi)從對"堅(jian)(jian)(jian)(jian)(jian)(jian)白(bai)(bai)石(shi)(shi)"的(de)(de)(de)(de)分析出發的(de)(de)(de)(de)。《公孫(sun)龍(long)子·堅(jian)(jian)(jian)(jian)(jian)(jian)白(bai)(bai)論(lun)(lun)》說(shuo):"視不(bu)(bu)得其(qi)(qi)所(suo)(suo)堅(jian)(jian)(jian)(jian)(jian)(jian)而(er)(er)(er)(er)得其(qi)(qi)所(suo)(suo)白(bai)(bai)者(zhe),無(wu)堅(jian)(jian)(jian)(jian)(jian)(jian)也;拊不(bu)(bu)得其(qi)(qi)所(suo)(suo)白(bai)(bai)而(er)(er)(er)(er)得其(qi)(qi)所(suo)(suo)堅(jian)(jian)(jian)(jian)(jian)(jian)者(zhe),無(wu)白(bai)(bai)也。"即人們用(yong)眼(yan)睛看(kan),不(bu)(bu)知(zhi)道它是(shi)(shi)(shi)(shi)堅(jian)(jian)(jian)(jian)(jian)(jian)硬(ying)(ying)的(de)(de)(de)(de),而(er)(er)(er)(er)知(zhi)道石(shi)(shi)是(shi)(shi)(shi)(shi)白(bai)(bai)顏(yan)(yan)(yan)色(se)(se)的(de)(de)(de)(de),這(zhe)就(jiu)(jiu)是(shi)(shi)(shi)(shi)沒有(you)堅(jian)(jian)(jian)(jian)(jian)(jian)硬(ying)(ying);用(yong)手摸不(bu)(bu)知(zhi)道它是(shi)(shi)(shi)(shi)白(bai)(bai)顏(yan)(yan)(yan)色(se)(se),而(er)(er)(er)(er)知(zhi)道它是(shi)(shi)(shi)(shi)堅(jian)(jian)(jian)(jian)(jian)(jian)硬(ying)(ying)的(de)(de)(de)(de),這(zhe)就(jiu)(jiu)是(shi)(shi)(shi)(shi)沒有(you)白(bai)(bai)顏(yan)(yan)(yan)色(se)(se)。在(zai)前一(yi)(yi)(yi)種(zhong)情(qing)(qing)(qing)況下(xia),堅(jian)(jian)(jian)(jian)(jian)(jian)硬(ying)(ying)藏(zang)(zang)了(le)起(qi)來。在(zai)后一(yi)(yi)(yi)種(zhong)情(qing)(qing)(qing)況下(xia),白(bai)(bai)色(se)(se)藏(zang)(zang)了(le)起(qi)來。這(zhe)叫作(zuo)"自藏(zang)(zang)"。《堅(jian)(jian)(jian)(jian)(jian)(jian)白(bai)(bai)論(lun)(lun)》又說(shuo):"得其(qi)(qi)白(bai)(bai),得其(qi)(qi)堅(jian)(jian)(jian)(jian)(jian)(jian),見(jian)(jian)(jian)與(yu)不(bu)(bu)見(jian)(jian)(jian)離(li)(li)(li)(li)。不(bu)(bu)見(jian)(jian)(jian)離(li)(li)(li)(li)一(yi)(yi)(yi)。一(yi)(yi)(yi)不(bu)(bu)相(xiang)盈,故(gu)離(li)(li)(li)(li)離(li)(li)(li)(li)也者(zhe),藏(zang)(zang)也。"看(kan)到它的(de)(de)(de)(de)白(bai)(bai)顏(yan)(yan)(yan)色(se)(se),摸到它的(de)(de)(de)(de)堅(jian)(jian)(jian)(jian)(jian)(jian)硬(ying)(ying),有(you)"見(jian)(jian)(jian)與(yu)不(bu)(bu)見(jian)(jian)(jian)"的(de)(de)(de)(de)情(qing)(qing)(qing)況,這(zhe)就(jiu)(jiu)叫離(li)(li)(li)(li),因為(wei)石(shi)(shi)與(yu)堅(jian)(jian)(jian)(jian)(jian)(jian)、白(bai)(bai)不(bu)(bu)能互(hu)相(xiang)包含(han),所(suo)(suo)以就(jiu)(jiu)分離(li)(li)(li)(li)了(le)。分離(li)(li)(li)(li)了(le)也就(jiu)(jiu)是(shi)(shi)(shi)(shi)藏(zang)(zang)起(qi)來了(le)。他認為(wei),"天(tian)下(xia)未有(you)若(ruo)堅(jian)(jian)(jian)(jian)(jian)(jian),而(er)(er)(er)(er)堅(jian)(jian)(jian)(jian)(jian)(jian)藏(zang)(zang)"。又說(shuo):"若(ruo)白(bai)(bai)者(zhe)必(bi)(bi)白(bai)(bai),則不(bu)(bu)白(bai)(bai)石(shi)(shi)物(wu)而(er)(er)(er)(er)白(bai)(bai)焉。""石(shi)(shi)其(qi)(qi)無(wu)有(you),惡取堅(jian)(jian)(jian)(jian)(jian)(jian)白(bai)(bai)乎?故(gu)離(li)(li)(li)(li)也。"這(zhe)是(shi)(shi)(shi)(shi)說(shuo),不(bu)(bu)使石(shi)(shi)與(yu)物(wu)變(bian)堅(jian)(jian)(jian)(jian)(jian)(jian)硬(ying)(ying)而(er)(er)(er)(er)獨立(li)的(de)(de)(de)(de)堅(jian)(jian)(jian)(jian)(jian)(jian)硬(ying)(ying)(即抽(chou)象的(de)(de)(de)(de)堅(jian)(jian)(jian)(jian)(jian)(jian)硬(ying)(ying)),天(tian)下(xia)是(shi)(shi)(shi)(shi)沒有(you)的(de)(de)(de)(de)。這(zhe)就(jiu)(jiu)是(shi)(shi)(shi)(shi)說(shuo),堅(jian)(jian)(jian)(jian)(jian)(jian)硬(ying)(ying)藏(zang)(zang)起(qi)來了(le)。若(ruo)白(bai)(bai)顏(yan)(yan)(yan)色(se)(se)本(ben)身(shen)定是(shi)(shi)(shi)(shi)白(bai)(bai)顏(yan)(yan)(yan)色(se)(se)的(de)(de)(de)(de)話,它就(jiu)(jiu)不(bu)(bu)必(bi)(bi)通過使物(wu)體發白(bai)(bai)而(er)(er)(er)(er)表現自己是(shi)(shi)(shi)(shi)白(bai)(bai)。他把本(ben)身(shen)是(shi)(shi)(shi)(shi)白(bai)(bai)顏(yan)(yan)(yan)色(se)(se)看(kan)成(cheng)(cheng)一(yi)(yi)(yi)種(zhong)抽(chou)象的(de)(de)(de)(de)白(bai)(bai)顏(yan)(yan)(yan)色(se)(se)。它看(kan)不(bu)(bu)見(jian)(jian)(jian),即是(shi)(shi)(shi)(shi)藏(zang)(zang)起(qi)來了(le)。石(shi)(shi)頭(tou)(tou)假(jia)如沒有(you)獨立(li)成(cheng)(cheng)為(wei)石(shi)(shi)的(de)(de)(de)(de)本(ben)領(ling),又怎么能夠(gou)形(xing)成(cheng)(cheng)既堅(jian)(jian)(jian)(jian)(jian)(jian)又白(bai)(bai)的(de)(de)(de)(de)石(shi)(shi)呢?因此,他的(de)(de)(de)(de)結論(lun)(lun)是(shi)(shi)(shi)(shi)白(bai)(bai)色(se)(se)與(yu)堅(jian)(jian)(jian)(jian)(jian)(jian)硬(ying)(ying)并不(bu)(bu)是(shi)(shi)(shi)(shi)結合在(zai)石(shi)(shi)頭(tou)(tou)里(li)面(mian),而(er)(er)(er)(er)是(shi)(shi)(shi)(shi)脫離(li)(li)(li)(li)石(shi)(shi)頭(tou)(tou)獨立(li)存(cun)在(zai)的(de)(de)(de)(de)。這(zhe)就(jiu)(jiu)是(shi)(shi)(shi)(shi)"離(li)(li)(li)(li)堅(jian)(jian)(jian)(jian)(jian)(jian)白(bai)(bai)"學(xue)說(shuo)的(de)(de)(de)(de)主要論(lun)(lun)點。這(zhe)一(yi)(yi)(yi)學(xue)說(shuo)把事物(wu)的(de)(de)(de)(de)各種(zhong)屬性(xing)一(yi)(yi)(yi)方(fang)面(mian)與(yu)物(wu)質實(shi)體割裂開,另一(yi)(yi)(yi)方(fang)面(mian)又把它們一(yi)(yi)(yi)一(yi)(yi)(yi)孤立(li)起(qi)來而(er)(er)(er)(er)否(fou)認其(qi)(qi)統一(yi)(yi)(yi)性(xing)。這(zhe)在(zai)哲學(xue)上就(jiu)(jiu)意味(wei)著一(yi)(yi)(yi)般不(bu)(bu)是(shi)(shi)(shi)(shi)存(cun)在(zai)個(ge)別之(zhi)中,而(er)(er)(er)(er)是(shi)(shi)(shi)(shi)可以脫離(li)(li)(li)(li)個(ge)別單獨存(cun)在(zai)的(de)(de)(de)(de)。公孫(sun)龍(long)"離(li)(li)(li)(li)堅(jian)(jian)(jian)(jian)(jian)(jian)白(bai)(bai)"學(xue)說(shuo)的(de)(de)(de)(de)詭辯性(xing)質,在(zai)他的(de)(de)(de)(de)"白(bai)(bai)馬非(fei)馬"的(de)(de)(de)(de)命題中表現最為(wei)明顯(xian)。
"白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)非(fei)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)"是(shi)(shi)(shi)古代思(si)想史上的(de)(de)(de)(de)著名(ming)命(ming)(ming)題。公孫龍的(de)(de)(de)(de)論證(zheng)是(shi)(shi)(shi)這(zhe)樣的(de)(de)(de)(de):"馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)者(zhe),所(suo)以命(ming)(ming)形(xing)也;白(bai)(bai)(bai)(bai)(bai)者(zhe)所(suo)以命(ming)(ming)色(se)(se)也。命(ming)(ming)色(se)(se)者(zhe)非(fei)命(ming)(ming)形(xing)也。故曰(yue):白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)非(fei)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)。"①"馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)"一(yi)(yi)(yi)(yi)詞(ci)是(shi)(shi)(shi)指(zhi)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)的(de)(de)(de)(de)形(xing)態,凡是(shi)(shi)(shi)具(ju)有馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)的(de)(de)(de)(de)形(xing)態的(de)(de)(de)(de)都命(ming)(ming)名(ming)為馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)。"白(bai)(bai)(bai)(bai)(bai)"一(yi)(yi)(yi)(yi)詞(ci)是(shi)(shi)(shi)指(zhi)白(bai)(bai)(bai)(bai)(bai)的(de)(de)(de)(de)顏(yan)色(se)(se),凡是(shi)(shi)(shi)白(bai)(bai)(bai)(bai)(bai)顏(yan)色(se)(se)的(de)(de)(de)(de)都命(ming)(ming)名(ming)為白(bai)(bai)(bai)(bai)(bai)。"白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)"是(shi)(shi)(shi)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)的(de)(de)(de)(de)形(xing)態再加上白(bai)(bai)(bai)(bai)(bai)的(de)(de)(de)(de)顏(yan)色(se)(se),亦即白(bai)(bai)(bai)(bai)(bai)顏(yan)色(se)(se)的(de)(de)(de)(de)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)。可(ke)見,馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)與(yu)(yu)白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)是(shi)(shi)(shi)兩個(ge)(ge)不同(tong)的(de)(de)(de)(de)概(gai)念,所(suo)以他(ta)說(shuo)(shuo):"白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)非(fei)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)"。這(zhe)是(shi)(shi)(shi)從(cong)概(gai)念的(de)(de)(de)(de)內涵方面(mian)來論證(zheng)的(de)(de)(de)(de)。其次,他(ta)又(you)從(cong)"馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)"與(yu)(yu)"白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)"的(de)(de)(de)(de)外延不同(tong)來論證(zheng)。他(ta)說(shuo)(shuo):"求(qiu)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma),黃、黑(hei)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)皆可(ke)致;求(qiu)白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma),黃、黑(hei)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)不可(ke)致"。②馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)一(yi)(yi)(yi)(yi)詞(ci)的(de)(de)(de)(de)外延包(bao)括一(yi)(yi)(yi)(yi)切馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)在內,所(suo)以黃馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)、黑(hei)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)都在內。白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)的(de)(de)(de)(de)外延僅限于白(bai)(bai)(bai)(bai)(bai)顏(yan)色(se)(se)的(de)(de)(de)(de)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma),所(suo)以黃馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)、黑(hei)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)不在內。馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)與(yu)(yu)白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)兩個(ge)(ge)概(gai)念既(ji)然有這(zhe)樣的(de)(de)(de)(de)差別,所(suo)以他(ta)說(shuo)(shuo):"白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)非(fei)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)"。第三,他(ta)又(you)從(cong)個(ge)(ge)別(個(ge)(ge)性(xing))與(yu)(yu)一(yi)(yi)(yi)(yi)般(ban)(共(gong)性(xing))的(de)(de)(de)(de)關系來論證(zheng)。他(ta)說(shuo)(shuo):"白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma),非(fei)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)也。白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)者(zhe),馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)與(yu)(yu)白(bai)(bai)(bai)(bai)(bai)也,白(bai)(bai)(bai)(bai)(bai)與(yu)(yu)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)也。故曰(yue):白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)非(fei)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)也。"③這(zhe)是(shi)(shi)(shi)說(shuo)(shuo),白(bai)(bai)(bai)(bai)(bai)是(shi)(shi)(shi)一(yi)(yi)(yi)(yi)切白(bai)(bai)(bai)(bai)(bai)色(se)(se)的(de)(de)(de)(de)共(gong)性(xing),而不是(shi)(shi)(shi)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma),馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)是(shi)(shi)(shi)一(yi)(yi)(yi)(yi)切馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)的(de)(de)(de)(de)共(gong)性(xing),而不是(shi)(shi)(shi)白(bai)(bai)(bai)(bai)(bai)。白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)指(zhi)白(bai)(bai)(bai)(bai)(bai)色(se)(se)的(de)(de)(de)(de)共(gong)性(xing)加上馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)的(de)(de)(de)(de)共(gong)性(xing)。所(suo)以白(bai)(bai)(bai)(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)并不是(shi)(shi)(shi)馬(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)(ma)。
公(gong)孫(sun)(sun)龍(long)的(de)(de)(de)(de)論(lun)證在邏輯上和概念(nian)分析上做出了(le)(le)獨(du)到的(de)(de)(de)(de)歷史貢獻,但是(shi)他把(ba)一(yi)(yi)(yi)(yi)些概念(nian)混淆而流入詭辯(bian)。他分析了(le)(le)馬與白(bai)馬這兩個(ge)(ge)概念(nian)的(de)(de)(de)(de)差別(bie)、個(ge)(ge)別(bie)與一(yi)(yi)(yi)(yi)般(ban)的(de)(de)(de)(de)差別(bie)。但是(shi),他夸(kua)大了(le)(le)這種差別(bie),把(ba)兩者(zhe)完(wan)全割裂開來,并(bing)加以絕對化(hua);最后達到否認個(ge)(ge)別(bie),只承認一(yi)(yi)(yi)(yi)般(ban),使一(yi)(yi)(yi)(yi)般(ban)脫(tuo)離個(ge)(ge)別(bie)獨(du)立存(cun)在。這樣,就把(ba)抽象(xiang)的(de)(de)(de)(de)概念(nian)當成脫(tuo)離具(ju)體事(shi)物的(de)(de)(de)(de)精神實體,從而導致了(le)(le)客觀唯心(xin)主義(yi)的(de)(de)(de)(de)結論(lun)。《莊子(zi)(zi)·天下》還記載了(le)(le)辯(bian)者(zhe)"二十一(yi)(yi)(yi)(yi)事(shi)",其中一(yi)(yi)(yi)(yi)些命(ming)題與公(gong)孫(sun)(sun)龍(long)有(you)關。如"雞三足",又見于《公(gong)孫(sun)(sun)龍(long)子(zi)(zi)·通變論(lun)》:"飛鳥之(zhi)景(jing),未嘗動(dong)也。"也是(shi)屬于公(gong)孫(sun)(sun)龍(long)一(yi)(yi)(yi)(yi)派的(de)(de)(de)(de)命(ming)題。景(jing)即影(ying)。這個(ge)(ge)命(ming)題是(shi)說,飛鳥的(de)(de)(de)(de)影(ying)子(zi)(zi)并(bing)沒有(you)在運動(dong)。在每一(yi)(yi)(yi)(yi)瞬(shun)間,飛鳥的(de)(de)(de)(de)影(ying)子(zi)(zi)可以認為是(shi)不動(dong)的(de)(de)(de)(de)。
但是(shi)(shi)時(shi)(shi)間有(you)連續性,空間有(you)延展性;飛鳥之影在(zai)時(shi)(shi)空體(ti)內(nei)又是(shi)(shi)運(yun)(yun)動著的。這個命(ming)題對運(yun)(yun)動的性質具有(you)片面的認識,但是(shi)(shi)最終是(shi)(shi)走上(shang)形(xing)而上(shang)學,否認運(yun)(yun)動的可能(neng)性。
名家(jia)是(shi)(shi)(shi)(shi)春(chun)秋戰(zhan)國社(she)會(hui)大(da)變革的(de)(de)(de)(de)(de)產物。他(ta)們(men)(men)的(de)(de)(de)(de)(de)辯論,"不(bu)法先王,不(bu)是(shi)(shi)(shi)(shi)禮義",①具有反傳(chuan)統的(de)(de)(de)(de)(de)精神,是(shi)(shi)(shi)(shi)為新的(de)(de)(de)(de)(de)政(zheng)權服務的(de)(de)(de)(de)(de)。但由于他(ta)們(men)(men)認識的(de)(de)(de)(de)(de)角度不(bu)同(tong)(tong),因此觀點有所不(bu)同(tong)(tong)。惠施、公(gong)孫(sun)龍都是(shi)(shi)(shi)(shi)片面(mian)夸大(da)了認識的(de)(de)(de)(de)(de)某一(yi)方(fang)面(mian),惠施強調事(shi)物的(de)(de)(de)(de)(de)"同(tong)(tong)一(yi)"(即同(tong)(tong))的(de)(de)(de)(de)(de)一(yi)方(fang)面(mian),公(gong)孫(sun)龍則強調事(shi)物的(de)(de)(de)(de)(de)差別(即"異")的(de)(de)(de)(de)(de)一(yi)方(fang)面(mian)。他(ta)們(men)(men)在各自所強調的(de)(de)(de)(de)(de)方(fang)面(mian)都有精辟(pi)的(de)(de)(de)(de)(de)思想(xiang),但是(shi)(shi)(shi)(shi)這(zhe)些認識卻受到形(xing)而上(shang)學思想(xiang)方(fang)法的(de)(de)(de)(de)(de)限制。他(ta)們(men)(men)的(de)(de)(de)(de)(de)錯誤是(shi)(shi)(shi)(shi)人類認識發(fa)展史上(shang)不(bu)可避免的(de)(de)(de)(de)(de),后(hou)期墨家(jia)的(de)(de)(de)(de)(de)邏輯思想(xiang)正是(shi)(shi)(shi)(shi)對他(ta)們(men)(men)的(de)(de)(de)(de)(de)批判總結。
但是,名(ming)家在(zai)歷史(shi)上是有貢獻的(de),他們非常有似于古希臘(la)的(de)智者派(pai),甚至于連某些命(ming)(ming)題(ti)都是相(xiang)似的(de)或者相(xiang)同的(de)(例(li)如公元前五世紀伊里亞的(de)芝(zhi)諾就有過"飛矢(shi)不動(dong)"的(de)命(ming)(ming)題(ti))。名(ming)辯學派(pai)和(he)智者派(pai)大(da)約前后同時各自(zi)在(zai)東方(fang)(fang)和(he)西方(fang)(fang)以幾乎(hu)相(xiang)同的(de)詭辯式的(de)理論活(huo)動(dong),參(can)與了當時歷史(shi)性的(de)社會大(da)變動(dong),并促使(shi)人類思想認識大(da)為(wei)深化。這(zhe)是人類文明史(shi)最值得引人注目的(de)現象之一(yi)。
公(gong)孫龍不像惠施(shi)那樣強(qiang)調相(xiang)對的(de)(de)(de)、變化的(de)(de)(de),而強(qiang)調“名”是絕(jue)對的(de)(de)(de)、不變的(de)(de)(de)。他(ta)由(you)此得到與(yu)柏拉(la)圖的(de)(de)(de)理(li)念(nian)或(huo)共相(xiang)相(xiang)同的(de)(de)(de)概念(nian),柏拉(la)圖的(de)(de)(de)理(li)念(nian)或(huo)共相(xiang)在西方哲學(xue)是極著名的(de)(de)(de)。
他的(de)著作《公(gong)孫龍子》,有一(yi)篇《白(bai)馬(ma)論》。其(qi)主(zhu)要命(ming)(ming)題是“白(bai)馬(ma)非馬(ma)”。公(gong)孫龍通過三(san)點(dian)(dian)論證,力(li)求證明這(zhe)個命(ming)(ming)題。第一(yi)點(dian)(dian)是:“馬(ma)者(zhe)。所以命(ming)(ming)形也(ye);白(bai)者(zhe),所以命(ming)(ming)色也(ye)。命(ming)(ming)色者(zhe)非命(ming)(ming)形也(ye)。故(gu)曰:白(bai)馬(ma)非馬(ma)。”若用西(xi)方邏輯學(xue)術語(yu),大(da)家可以說(shuo),這(zhe)一(yi)點(dian)(dian)是強(qiang)調,“馬(ma)”、“白(bai)”、“白(bai)馬(ma)”的(de)內(nei)涵(han)(han)(han)的(de)不同。“馬(ma)”的(de)內(nei)涵(han)(han)(han)是一(yi)種動物,“白(bai)”的(de)內(nei)涵(han)(han)(han)是一(yi)種顏色,“白(bai)馬(ma)”的(de)內(nei)涵(han)(han)(han)是一(yi)種動物加一(yi)種顏色。三(san)者(zhe)內(nei)涵(han)(han)(han)各不相同,所以白(bai)馬(ma)非馬(ma)。
第二點是(shi)(shi):“求馬(ma)(ma),黃(huang)(huang)黑(hei)(hei)馬(ma)(ma)皆(jie)可(ke)致。求白(bai)馬(ma)(ma),黃(huang)(huang)黑(hei)(hei)馬(ma)(ma)不(bu)(bu)(bu)可(ke)致。……故(gu)黃(huang)(huang)黑(hei)(hei)馬(ma)(ma)一也(ye)(ye),而可(ke)以(yi)(yi)(yi)應(ying)有(you)馬(ma)(ma),而不(bu)(bu)(bu)可(ke)以(yi)(yi)(yi)應(ying)有(you)白(bai)馬(ma)(ma),是(shi)(shi)白(bai)馬(ma)(ma)之非(fei)(fei)馬(ma)(ma)審矣”。“馬(ma)(ma)者(zhe),無去(qu)取于(yu)(yu)色(se),故(gu)黃(huang)(huang)黑(hei)(hei)皆(jie)所以(yi)(yi)(yi)應(ying)。白(bai)馬(ma)(ma)者(zhe)有(you)去(qu)取于(yu)(yu)色(se),黃(huang)(huang)黑(hei)(hei)馬(ma)(ma)皆(jie)所以(yi)(yi)(yi)色(se)去(qu),故(gu)惟白(bai)馬(ma)(ma)獨可(ke)以(yi)(yi)(yi)應(ying)耳。無去(qu)者(zhe),非(fei)(fei)有(you)去(qu)也(ye)(ye)。故(gu)曰:白(bai)馬(ma)(ma)非(fei)(fei)馬(ma)(ma)”。若用西方邏輯學術語,我們可(ke)以(yi)(yi)(yi)說,這一點是(shi)(shi)強調(diao),“馬(ma)(ma)”、“白(bai)馬(ma)(ma)”的(de)外延(yan)的(de)不(bu)(bu)(bu)同(tong)。“馬(ma)(ma)”的(de)外延(yan)包括(kuo)一切(qie)馬(ma)(ma),不(bu)(bu)(bu)管其顏(yan)色(se)的(de)區別。“白(bai)馬(ma)(ma)”的(de)外延(yan)只包括(kuo)白(bai)馬(ma)(ma),有(you)相應(ying)的(de)顏(yan)色(se)區別。由于(yu)(yu)“馬(ma)(ma)”與“白(bai)馬(ma)(ma)”外延(yan)不(bu)(bu)(bu)同(tong),所以(yi)(yi)(yi)白(bai)馬(ma)(ma)非(fei)(fei)馬(ma)(ma)。
第三(san)點是:“馬(ma)(ma)(ma)(ma)(ma)固有色(se)(se),故(gu)有白(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)。使馬(ma)(ma)(ma)(ma)(ma)無色(se)(se),有馬(ma)(ma)(ma)(ma)(ma)如己耳。安(an)取白(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)?故(gu)白(bai)(bai)者,非(fei)馬(ma)(ma)(ma)(ma)(ma)也。白(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)者,馬(ma)(ma)(ma)(ma)(ma)與(yu)白(bai)(bai)也,白(bai)(bai)與(yu)馬(ma)(ma)(ma)(ma)(ma)也。故(gu)曰:白(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)非(fei)馬(ma)(ma)(ma)(ma)(ma)也。”這一點似(si)乎是強調,“馬(ma)(ma)(ma)(ma)(ma)”這個(ge)共(gong)性(xing)(xing)與(yu)“白(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)”這個(ge)共(gong)性(xing)(xing)的(de)(de)(de)不(bu)同(tong)。馬(ma)(ma)(ma)(ma)(ma)的(de)(de)(de)共(gong)性(xing)(xing),是一切馬(ma)(ma)(ma)(ma)(ma)的(de)(de)(de)本(ben)質屬性(xing)(xing)。它(ta)不(bu)包涵顏色(se)(se),僅只是“馬(ma)(ma)(ma)(ma)(ma)作(zuo)為(wei)馬(ma)(ma)(ma)(ma)(ma)”。這樣的(de)(de)(de)“馬(ma)(ma)(ma)(ma)(ma)”的(de)(de)(de)共(gong)性(xing)(xing)與(yu)“白(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)”的(de)(de)(de)共(gong)性(xing)(xing)不(bu)同(tong)。也就是說,馬(ma)(ma)(ma)(ma)(ma)作(zuo)為(wei)馬(ma)(ma)(ma)(ma)(ma)與(yu)白(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)作(zuo)為(wei)白(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)不(bu)同(tong)。所(suo)以白(bai)(bai)馬(ma)(ma)(ma)(ma)(ma)非(fei)馬(ma)(ma)(ma)(ma)(ma)。
或“堅(jian)(jian)(jian)石(shi)(shi)”,除了馬(ma)作(zuo)為馬(ma),又還有(you)(you)白(bai)(bai)(bai)(bai)(bai)(bai)作(zuo)為白(bai)(bai)(bai)(bai)(bai)(bai),即白(bai)(bai)(bai)(bai)(bai)(bai)的(de)共相。《白(bai)(bai)(bai)(bai)(bai)(bai)馬(ma)論》中說:“白(bai)(bai)(bai)(bai)(bai)(bai)者(zhe)不(bu)定(ding)所(suo)(suo)(suo)(suo)白(bai)(bai)(bai)(bai)(bai)(bai),忘之而(er)可(ke)也(ye)(ye)。白(bai)(bai)(bai)(bai)(bai)(bai)馬(ma)者(zhe)言白(bai)(bai)(bai)(bai)(bai)(bai)。定(ding)所(suo)(suo)(suo)(suo)白(bai)(bai)(bai)(bai)(bai)(bai)也(ye)(ye)。定(ding)所(suo)(suo)(suo)(suo)白(bai)(bai)(bai)(bai)(bai)(bai)者(zhe),非白(bai)(bai)(bai)(bai)(bai)(bai)也(ye)(ye)。”定(ding)所(suo)(suo)(suo)(suo)白(bai)(bai)(bai)(bai)(bai)(bai),就是(shi)(shi)具體(ti)(ti)(ti)的(de)白(bai)(bai)(bai)(bai)(bai)(bai)色,見于(yu)各(ge)種(zhong)實際的(de)白(bai)(bai)(bai)(bai)(bai)(bai)色物體(ti)(ti)(ti)。見于(yu)各(ge)種(zhong)實際白(bai)(bai)(bai)(bai)(bai)(bai)色物體(ti)(ti)(ti)的(de)白(bai)(bai)(bai)(bai)(bai)(bai)色,是(shi)(shi)這些物體(ti)(ti)(ti)所(suo)(suo)(suo)(suo)定(ding)的(de)。但是(shi)(shi)“白(bai)(bai)(bai)(bai)(bai)(bai)”的(de)共相,則(ze)不(bu)是(shi)(shi)任何(he)實際的(de)白(bai)(bai)(bai)(bai)(bai)(bai)色物體(ti)(ti)(ti)所(suo)(suo)(suo)(suo)定(ding)。它(ta)是(shi)(shi)未(wei)定(ding)的(de)白(bai)(bai)(bai)(bai)(bai)(bai)的(de)共性。《公孫龍子》另有(you)(you)一篇《堅(jian)(jian)(jian)白(bai)(bai)(bai)(bai)(bai)(bai)論》。其(qi)(qi)(qi)主要命題是(shi)(shi)“離堅(jian)(jian)(jian)白(bai)(bai)(bai)(bai)(bai)(bai)”。公孫龍的(de)證明有(you)(you)兩個部(bu)分(fen)。第一部(bu)分(fen)是(shi)(shi),假設有(you)(you)堅(jian)(jian)(jian)而(er)白(bai)(bai)(bai)(bai)(bai)(bai)的(de)石(shi)(shi),他設問說:“堅(jian)(jian)(jian)、白(bai)(bai)(bai)(bai)(bai)(bai)、石(shi)(shi):三(san),可(ke)乎?曰(yue)(yue)(yue)(yue):不(bu)可(ke)。曰(yue)(yue)(yue)(yue):二(er)(er),可(ke)乎?曰(yue)(yue)(yue)(yue):可(ke)。曰(yue)(yue)(yue)(yue):何(he)哉?曰(yue)(yue)(yue)(yue):無(wu)堅(jian)(jian)(jian)得(de)白(bai)(bai)(bai)(bai)(bai)(bai),其(qi)(qi)(qi)舉(ju)也(ye)(ye)二(er)(er);無(wu)白(bai)(bai)(bai)(bai)(bai)(bai)得(de)堅(jian)(jian)(jian),其(qi)(qi)(qi)舉(ju)也(ye)(ye)二(er)(er)”。“視不(bu)得(de)其(qi)(qi)(qi)所(suo)(suo)(suo)(suo)堅(jian)(jian)(jian)而(er)得(de)其(qi)(qi)(qi)所(suo)(suo)(suo)(suo)白(bai)(bai)(bai)(bai)(bai)(bai)者(zhe),無(wu)堅(jian)(jian)(jian)也(ye)(ye)。拊不(bu)得(de)其(qi)(qi)(qi)所(suo)(suo)(suo)(suo)白(bai)(bai)(bai)(bai)(bai)(bai)而(er)得(de)其(qi)(qi)(qi)所(suo)(suo)(suo)(suo)堅(jian)(jian)(jian),得(de)其(qi)(qi)(qi)堅(jian)(jian)(jian)也(ye)(ye),無(wu)白(bai)(bai)(bai)(bai)(bai)(bai)也(ye)(ye)。”這段(duan)對話是(shi)(shi)從知識論方面證明堅(jian)(jian)(jian)、白(bai)(bai)(bai)(bai)(bai)(bai)是(shi)(shi)彼此分(fen)離的(de)。有(you)(you)一堅(jian)(jian)(jian)白(bai)(bai)(bai)(bai)(bai)(bai)石(shi)(shi),用眼(yan)看,則(ze)只“得(de)其(qi)(qi)(qi)所(suo)(suo)(suo)(suo)白(bai)(bai)(bai)(bai)(bai)(bai)”,只得(de)一白(bai)(bai)(bai)(bai)(bai)(bai)石(shi)(shi);用手摸,則(ze)只“得(de)其(qi)(qi)(qi)所(suo)(suo)(suo)(suo)堅(jian)(jian)(jian)”,只得(de)一堅(jian)(jian)(jian)石(shi)(shi)。感覺(jue)白(bai)(bai)(bai)(bai)(bai)(bai)時不(bu)能感覺(jue)堅(jian)(jian)(jian),感覺(jue)堅(jian)(jian)(jian)時不(bu)能感覺(jue)白(bai)(bai)(bai)(bai)(bai)(bai)。所(suo)(suo)(suo)(suo)以,從知識論方面說,只有(you)(you)“白(bai)(bai)(bai)(bai)(bai)(bai)石(shi)(shi)”沒有(you)(you)“堅(jian)(jian)(jian)白(bai)(bai)(bai)(bai)(bai)(bai)石(shi)(shi)”。這就是(shi)(shi)“無(wu)堅(jian)(jian)(jian)得(de)白(bai)(bai)(bai)(bai)(bai)(bai),其(qi)(qi)(qi)舉(ju)也(ye)(ye)二(er)(er);無(wu)白(bai)(bai)(bai)(bai)(bai)(bai)得(de)堅(jian)(jian)(jian),其(qi)(qi)(qi)舉(ju)也(ye)(ye)二(er)(er)”的(de)意思。
他(ta)(ta)(ta)的(de)(de)(de)關于名與(yu)(yu)實的(de)(de)(de)關系(xi)的(de)(de)(de)理(li)論是(shi)(shi)(shi)建立(li)在(zai)(zai)他(ta)(ta)(ta)的(de)(de)(de)關于共相(xiang)(xiang)(xiang)的(de)(de)(de)唯(wei)心(xin)主(zhu)義哲學理(li)論之上(shang)(shang)的(de)(de)(de)。他(ta)(ta)(ta)認為(wei),共相(xiang)(xiang)(xiang)是(shi)(shi)(shi)一(yi)(yi)種獨立(li)存在(zai)(zai)。他(ta)(ta)(ta)的(de)(de)(de)“堅(jian)(jian)(jian)(jian)白(bai)(bai)(bai)論”就(jiu)是(shi)(shi)(shi)企圖(tu)論證一(yi)(yi)塊(kuai)白(bai)(bai)(bai)石頭的(de)(de)(de)白(bai)(bai)(bai)色(se)(se)和(he)堅(jian)(jian)(jian)(jian)硬(ying)(ying)(ying)性(xing)是(shi)(shi)(shi)可以(yi)獨立(li)存在(zai)(zai)的(de)(de)(de)。他(ta)(ta)(ta)首先從關于“堅(jian)(jian)(jian)(jian)白(bai)(bai)(bai)石”的(de)(de)(de)感(gan)(gan)覺(jue)(jue)(jue)來進(jin)行分(fen)析,企圖(tu)說(shuo)(shuo)明(ming),“堅(jian)(jian)(jian)(jian)”與(yu)(yu)“白(bai)(bai)(bai)”可以(yi)互相(xiang)(xiang)(xiang)分(fen)離(li)(li)(li),然后(hou)再說(shuo)(shuo)明(ming)它們可以(yi)離(li)(li)(li)開(kai)人們的(de)(de)(de)意(yi)識(shi)而(er)存在(zai)(zai)。他(ta)(ta)(ta)說(shuo)(shuo):“視不(bu)(bu)得其(qi)(qi)所(suo)(suo)堅(jian)(jian)(jian)(jian)而(er)得其(qi)(qi)所(suo)(suo)白(bai)(bai)(bai)者(zhe),無堅(jian)(jian)(jian)(jian)也(ye)(ye)(ye)(ye)。,拊(fu)不(bu)(bu)得其(qi)(qi)所(suo)(suo)白(bai)(bai)(bai)而(er)得其(qi)(qi)所(suo)(suo)堅(jian)(jian)(jian)(jian)者(zhe),無白(bai)(bai)(bai)也(ye)(ye)(ye)(ye)。”(《堅(jian)(jian)(jian)(jian)白(bai)(bai)(bai)論》)又說(shuo)(shuo):“得其(qi)(qi)白(bai)(bai)(bai).得其(qi)(qi)堅(jian)(jian)(jian)(jian),見(jian)(jian)(jian)(jian)與(yu)(yu)不(bu)(bu)見(jian)(jian)(jian)(jian)離(li)(li)(li):不(bu)(bu)見(jian)(jian)(jian)(jian)離(li)(li)(li)。一(yi)(yi)一(yi)(yi)不(bu)(bu)相(xiang)(xiang)(xiang)盈故離(li)(li)(li),離(li)(li)(li)也(ye)(ye)(ye)(ye)者(zhe)藏(zang)(zang)也(ye)(ye)(ye)(ye)。”(同上(shang)(shang))這(zhe)(zhe)(zhe)是(shi)(shi)(shi)說(shuo)(shuo),看(kan)的(de)(de)(de)時候(hou)感(gan)(gan)覺(jue)(jue)(jue)不(bu)(bu)到(dao)堅(jian)(jian)(jian)(jian)硬(ying)(ying)(ying)性(xing),而(er)只感(gan)(gan)覺(jue)(jue)(jue)到(dao)白(bai)(bai)(bai)色(se)(se),這(zhe)(zhe)(zhe)時候(hou)堅(jian)(jian)(jian)(jian)硬(ying)(ying)(ying)性(xing)等于沒有(you)。觸的(de)(de)(de)時候(hou)感(gan)(gan)覺(jue)(jue)(jue)不(bu)(bu)到(dao)白(bai)(bai)(bai)色(se)(se),而(er)只感(gan)(gan)覺(jue)(jue)(jue)到(dao)堅(jian)(jian)(jian)(jian)硬(ying)(ying)(ying)性(xing),這(zhe)(zhe)(zhe)時候(hou)白(bai)(bai)(bai)色(se)(se)等于沒有(you)。或者(zhe)感(gan)(gan)覺(jue)(jue)(jue)到(dao)白(bai)(bai)(bai)色(se)(se),或者(zhe)感(gan)(gan)覺(jue)(jue)(jue)到(dao)堅(jian)(jian)(jian)(jian)硬(ying)(ying)(ying)性(xing)。感(gan)(gan)覺(jue)(jue)(jue)到(dao)的(de)(de)(de)與(yu)(yu)感(gan)(gan)覺(jue)(jue)(jue)不(bu)(bu)到(dao)的(de)(de)(de)是(shi)(shi)(shi)彼(bi)(bi)此分(fen)離(li)(li)(li)的(de)(de)(de)。彼(bi)(bi)此不(bu)(bu)聯(lian)在(zai)(zai)一(yi)(yi)起,所(suo)(suo)以(yi)說(shuo)(shuo)是(shi)(shi)(shi)分(fen)離(li)(li)(li)。而(er)分(fen)離(li)(li)(li)就(jiu)是(shi)(shi)(shi)藏(zang)(zang)在(zai)(zai)自身(shen)(shen)(shen)之中。(公孫龍(long)自己解釋說(shuo)(shuo)“藏(zang)(zang)”是(shi)(shi)(shi)指(zhi)“自藏(zang)(zang)”有(you)相(xiang)(xiang)(xiang)當于“潛存”之意(yi))公孫龍(long)的(de)(de)(de)這(zhe)(zhe)(zhe)兩(liang)段話是(shi)(shi)(shi)說(shuo)(shuo)堅(jian)(jian)(jian)(jian)白(bai)(bai)(bai)石的(de)(de)(de)白(bai)(bai)(bai)色(se)(se)和(he)堅(jian)(jian)(jian)(jian)硬(ying)(ying)(ying)性(xing)是(shi)(shi)(shi)可以(yi)彼(bi)(bi)此分(fen)離(li)(li)(li)而(er)存在(zai)(zai)的(de)(de)(de)。他(ta)(ta)(ta)又說(shuo)(shuo):“且(qie)猶白(bai)(bai)(bai),以(yi)目(mu),以(yi)火見(jian)(jian)(jian)(jian),而(er)火不(bu)(bu)見(jian)(jian)(jian)(jian);則火與(yu)(yu)目(mu)不(bu)(bu)見(jian)(jian)(jian)(jian)而(er)神(shen)見(jian)(jian)(jian)(jian)。神(shen)不(bu)(bu)見(jian)(jian)(jian)(jian),而(er)見(jian)(jian)(jian)(jian)離(li)(li)(li)。”(同上(shang)(shang))這(zhe)(zhe)(zhe)里(li)所(suo)(suo)說(shuo)(shuo)的(de)(de)(de)“神(shen)”即(ji)精神(shen)作(zuo)用,也(ye)(ye)(ye)(ye)就(jiu)是(shi)(shi)(shi)指(zhi)意(yi)識(shi);“火”就(jiu)是(shi)(shi)(shi)光(guang)(guang)(guang)。這(zhe)(zhe)(zhe)是(shi)(shi)(shi)說(shuo)(shuo),例如白(bai)(bai)(bai)色(se)(se)是(shi)(shi)(shi)靠(kao)著眼睛和(he)光(guang)(guang)(guang)看(kan)見(jian)(jian)(jian)(jian)的(de)(de)(de)。但光(guang)(guang)(guang)本身(shen)(shen)(shen)沒有(you)見(jian)(jian)(jian)(jian)物(wu)(wu)的(de)(de)(de)作(zuo)用,那么光(guang)(guang)(guang)和(he)眼睛合在(zai)(zai)一(yi)(yi)起也(ye)(ye)(ye)(ye)不(bu)(bu)能(neng)看(kan)見(jian)(jian)(jian)(jian),只能(neng)是(shi)(shi)(shi)意(yi)識(shi)在(zai)(zai)看(kan)見(jian)(jian)(jian)(jian),而(er)意(yi)識(shi)本身(shen)(shen)(shen)也(ye)(ye)(ye)(ye)是(shi)(shi)(shi)沒有(you)見(jian)(jian)(jian)(jian)物(wu)(wu)作(zuo)用的(de)(de)(de)。所(suo)(suo)以(yi)白(bai)(bai)(bai)色(se)(se)是(shi)(shi)(shi)和(he)視覺(jue)(jue)(jue)分(fen)離(li)(li)(li)著的(de)(de)(de)。公孫龍(long)在(zai)(zai)這(zhe)(zhe)(zhe)里(li)是(shi)(shi)(shi)在(zai)(zai)說(shuo)(shuo)明(ming)白(bai)(bai)(bai)色(se)(se)等共相(xiang)(xiang)(xiang)是(shi)(shi)(shi)可以(yi)離(li)(li)(li)開(kai)人類的(de)(de)(de)感(gan)(gan)覺(jue)(jue)(jue)而(er)獨立(li)存在(zai)(zai)的(de)(de)(de)。(公孫龍(long)在(zai)(zai)這(zhe)(zhe)(zhe)里(li)犯了一(yi)(yi)些邏(luo)輯錯誤。因為(wei)由(you)(you)眼睛離(li)(li)(li)開(kai)了光(guang)(guang)(guang)不(bu)(bu)能(neng)見(jian)(jian)(jian)(jian)物(wu)(wu)和(he)光(guang)(guang)(guang)本身(shen)(shen)(shen)沒有(you)見(jian)(jian)(jian)(jian)物(wu)(wu)作(zuo)用這(zhe)(zhe)(zhe)樣的(de)(de)(de)前提,不(bu)(bu)能(neng)推出,眼睛和(he)光(guang)(guang)(guang)合在(zai)(zai)一(yi)(yi)起也(ye)(ye)(ye)(ye)不(bu)(bu)能(neng)看(kan)見(jian)(jian)(jian)(jian)。)由(you)(you)這(zhe)(zhe)(zhe)一(yi)(yi)些話可以(yi)清(qing)楚(chu)地看(kan)出來,公孫龍(long)主(zhu)張像(xiang)“白(bai)(bai)(bai)色(se)(se)”這(zhe)(zhe)(zhe)一(yi)(yi)類共相(xiang)(xiang)(xiang)是(shi)(shi)(shi)客觀存在(zai)(zai)的(de)(de)(de),因之他(ta)(ta)(ta)是(shi)(shi)(shi)客觀唯(wei)心(xin)主(zhu)義者(zhe)。
公(gong)孫(sun)龍(long)觀察事(shi)物,雖然把個別與(yu)一(yi)般用"離"的(de)(de)觀點絕(jue)對(dui)化(hua),只見離而(er)不(bu)(bu)見合,不(bu)(bu)符合辯(bian)證法的(de)(de)“個別存在(zai)于(yu)一(yi)般之中(zhong)”的(de)(de)觀點,但他能夠開辟(pi)邏輯(ji)(ji)領域,建立(li)邏輯(ji)(ji)學(xue)的(de)(de)理論體系,有助于(yu)百家(jia)爭鳴的(de)(de)發(fa)展(zhan)。中(zhong)國歷史上多(duo)數學(xue)派看重研究政(zheng)治倫理,多(duo)不(bu)(bu)懂(dong)邏輯(ji)(ji)學(xue),甚(shen)至(zhi)不(bu)(bu)承認(ren)這門學(xue)問,往往以政(zheng)治倫理觀念來批(pi)評公(gong)孫(sun)龍(long)的(de)(de)邏輯(ji)(ji)思想,直到(dao)近世人們才公(gong)開承認(ren)公(gong)孫(sun)龍(long)辯(bian)學(xue)對(dui)象邏輯(ji)(ji)的(de)(de)問題,并加以重視。
公孫龍“白馬(ma)非馬(ma)”的(de)論說(shuo)雖(sui)然有其一定的(de)合理性和開(kai)創(chuang)性,也(ye)符合辯證(zheng)法講的(de)個別與(yu)一般(ban)相區別的(de)原理,更有糾正當時名(ming)實混亂的(de)作用。但是(shi),他沿(yan)著同樣的(de)原理隨后再提出的(de)“雞三足”、“火(huo)不熱(re)”等辯說(shuo)確有走火(huo)入(ru)魔之嫌,已墜入(ru)“詭辯”的(de)深淵中。怪不得(de)荀子要斥他為“此惑于用名(ming)以亂實也(ye)。”鄒衍要批評他是(shi)“害(hai)大道”、“不能無害(hai)君子”。
諸子各家普遍認為(wei)(wei)公孫龍為(wei)(wei)詭辯(bian),又似乎無(wu)法(fa)在辯(bian)論(lun)中勝出。
《公孫(sun)龍子》第一(yi)章《跡府(fu)》記載了孔(kong)子的(de)后(hou)代孔(kong)穿企(qi)圖駁(bo)倒公孫(sun)龍但失敗的(de)故事。
《莊(zhuang)子天(tian)下(xia)篇》稱公(gong)孫(sun)龍“飾(shi)人(ren)(ren)之(zhi)心,易(yi)人(ren)(ren)之(zhi)意,能(neng)勝人(ren)(ren)之(zhi)口,不能(neng)服人(ren)(ren)之(zhi)心”。
《荀子 不(bu)茍篇》中認為君子不(bu)看重(zhong)惠施(shi)等名家的辯(bian)才,因為其不(bu)符合(he)禮。君子并不(bu)是無法反(fan)駁堅白離的觀點,而是不(bu)與之(zhi)辯(bian)論。
《荀(xun)子 正名(ming)篇》認為白(bai)馬非馬論(lun)是“此惑于(yu)用名(ming)以(yi)亂實者也”。
《資治通(tong)鑒(jian)》中記載(zai)鄒衍認(ren)為公(gong)孫龍是“煩文以相(xiang)假,飾辭以相(xiang)敦,巧譬以相(xiang)移,引人使不得(de)及其意,如此害大道”,于是不和公(gong)孫龍辯(bian)論。
周昌忠《公孫龍(long)(long)子新(xin)論》把(ba)公孫龍(long)(long)的思(si)想和西方哲學(xue)相比(bi)較,認為公孫龍(long)(long)“構造了一個(ge)相當豐富的關于(yu)語言本身的哲學(xue)理論”,并不比(bi)亞里士(shi)多德遜色。
張遠山在著作《寓(yu)言的密碼》中(zhong)認為,公孫龍開(kai)創了中(zhong)國的理性學派的先河。但諸子百家(jia)都未(wei)能(neng)理解他的觀點。